The fabrication of certain ceramic honeycomb structures from ceramic-forming powder mixtures is known. Plasticized mixtures are forced through extrusion dies to form lengths of wet extrudate which are then dried and fired to convert the extruded mixture to strong refractory ceramic materials.
Honeycomb structures can be square or closed cylindrical (circular, oval, elliptical, racetrack) cross-sections transverse to the axis of extrusion and direction of channel orientation in the bodies. The honeycomb channels, which may be of square, triangular, hexagonal, or other cross-sectional shape, are bounded by thin channel walls and can be present in channel densities of, for example, from 15 to 100 channels per cm2 of honeycomb cross-sectional area.
Geometries and materials provide ceramic honeycomb structures with relatively high strength and durability after firing. However, the wet honeycomb extrudate produced earlier in the process is relatively quite soft and subject to damage in the course of further handling, particularly until it has been dried.
Handling can cause shape distortion in wet honeycomb shapes comprising thin web and skin structures, or where especially large and heavy extrudate sections need to be transported. Further, extrudate sections of large diameter or frontal area transverse to the axis of extrusion can suffer from distortion and collapse of the honeycomb channel structure as that structure must bear the weight and withstand the lateral weight shifts of the upper structure in the course of transport.